Field
Embodiments of the inventive concepts relate to overlay marks used in semiconductor device fabrication, methods of forming the same, and methods of fabricating semiconductor devices using the same.
Description of Related Art
Processes of fabricating semiconductor devices have become more elaborate due to an increasing degree of integration of semiconductor devices. Therefore, an alignment process performed before a photolithography process and an overlay inspection process performed after the photolithography process may both require increased precision. The overlay inspection process is a process that inspects whether a pattern disposed at a lower level and a pattern disposed at a higher level are formed to be appropriately aligned. The overlay inspection process may become more difficult as a stack height of the semiconductor device is gradually increased. For example, it may be difficult to distinguish an overlay mark formed at a lower level because of the height of the highly stacked materials.